Finding the Fourth Proportional to 2,387.15, 3,578.56 and 847.79

Step by Step Solution

1. Step 1: Write the proportion equation
   2,387.15 : 3,578.56 = 847.79 : x
2. Step 2: Convert to fraction form
   2,387.15/3,578.56 = 847.79/x
3. Step 3: Cross multiply
   2,387.15x = 3,578.56 × 847.79
4. Step 4: Simplify right side
   2,387.15x = 3,033,845.25
5. Step 5: Solve for x
   x = 3,033,845.25/2,387.15
6. Step 6: Final answer
   x = 1,270.91